N-bis(p-dialkylaminophenyl)methyl sulfonamides



N-BIS(p-l) IALKYLAMINOPHENYDMETHYL SULFONAMIDES Frederick H. Kranz,Bufialo, N.Y., assignor to Allied Chemical Corporation, New York, N.Y.,a corporation of New York No Drawing. Filed May 12, 1958, Ser. No.734,419

14 Claims. (Cl. 260-556) This invention relates to compounds which arederivatives of. bis(p-dialkylaminoaryl)methane in which nitrogen islinked to the methane carbon atom. It relates more particularly tocompounds of said type having superior properties as compared to knowncompounds of said general class.

An object of the present invention is to provide novel derivatives ofbis(p-dialkylaminoaryl)methane, and especially ofbis(p-dimethylaminophenyl)methane, in which the methane carbon atomthereof is linked to the nitrogen atom of a nitrogen-containing radicalhaving a beneficial effect upon the properties of said derivatives.

A further object of the present invention is to pro vide novelbis(p-dialkylaminoaryl) methyl derivatives of said type which arelightly colored or substantially colorless but which when contacted withacidic electron acceptors produce colored compositions.

Another object of the present invention is to provide novel compounds ofsaid type having superior stability as compared to N-bis(p-dimethylaminophenyl)methyl aniline (also known as N-phenylleucoauramine) and derivatives of the latter, when embodied in manifoldrecord systems of the type disclosed in US. Patents 2,505,470 and2,548,366, for example.

Other objects of the invention will in part be obvious and will in partappear hereinafter.

It is known that derivatives of benzhydrol and such compounds ascrystalline violet lactone, when dissolved in non-polar solvents, suchas, benzene, toluene or chlorinated biphenyl, and brought into contactwith acidic electron acceptors such as kaolin, bentonite, attapulgite,silica gel, felspar, pyrophyllite, halloysite, magnesium trisilicateZinc sulphate, zinc sulfide, calcium, fluoride, and calcium citrate, aswell as organic acids such as tannic acid and benzoic acid, turn fromcolorless to a deep blue or violet shade.

Compounds which are derivatives of bis(p-dimethylaminophenyl)methane inwhich the nitrogen atom of a phenylamino radical replaces one of themethane hydrogen atoms, such as N-phenyl leucoaurarnine, i.e., Nbis(pdimethylaminophenyl)methyl aniline, are known .com-

pounds which are colorless or substantially colorless, but

which constitute color-reactants of the electron donor type since theyturn blue on coming into absorptive contact with acidic electronacceptor materials such as acidic clays (for example, attapulgite,halloysite, kaolin.

and bentonite), as well as aluminum sulfate, zeolite material, silicagel, magnesium trisilicate, and Zinc sulphide, among others. They havebeen proposed for use heretofore in solution in toluene or chlorinatedbiphenyl for printing in color on paper or other material coated orfilled with such acidic materials. Thus, they have been proposed for usein so-called colorless carbon papers, impact printing papers andduplicating manifold record systems, for example, of the type disclosedin U.S.P. 2,505,470, wherein a solution of the N-bis(p-dimethy1- 2aminophenyl)methyl aniline is provided in the form of discrete particlesin conjunction with a sohd lnsulatmg material including an organichydrophilic film-forming material and an acidic clay which, uponpressure by a stylus or impact, as by a typewriter key, causescombination of the color-forming reactant with the clay and a resultingcolored mark; and, for example, of the type disclosed in U.S.P.2,548,366, wherein the rear surface of each top sheet of a series ofoverlying sheets is coated.

with a dispersion of a suitable solution of the N-bis(p-dimethylaminophenyl)methyl aniline in a rupturable hydrophiliccolloid film, and the adjacent top surface of the next underlying sheetis coated or filled with an electronacceptor acidic material, so thatpressure of a stylus or impact upon the top sheet causes color formationon the surface containing the acidic material at the points 1 ofpressure or impact. I

I have discovered that sulfonamide derivatives of bis-f(p-dimethylaminophenyl)methane and related compounds, in which thenitrogen atom of a sulfonamide replaces one of the methane hydrogenatoms, possess advantageous properties which render them particularlyuseful in systems of the above type.

The compounds of the present invention areN-bis(pdialkylaminoaryl)methyl sulfonamides in which the alkyl groups ofthe dialkylamino radical each have 1 to 5 carbon atoms, and the arylradicals are mononuclear aryl radicals. They include compounds which inthemselves are colored (containing chromophoric groups) and compoundswhich are lightly colored, or colorless, or substantially colorless(free from chromophoric groups). Further, they include compounds whichinclude in their molecules acidic groups containing a hydrogen cation(for example, a sulfonic acid or carboxylic acid radical), and compoundsfree from such acidic groups. In this connection it is noted that groupswhich do not contain a hydrogen cation, such as salts of acidic groups(e.g.,

alkali metal, ammonium, organic base and other salts of carboxylic andsulfonic acids) are included herein as being free from'acid groupscontaining a free hydrogen cation.

colorless in the solid form (leuco form), which renders them of specialutility in the manufacture of impact printing and duplicating materialsof the types referred to above.

The alkyl radicals of the p-dialkylamino radicals ome Commethyl, ethyl,propyl, butyl and amyl radicals. pounds in which they are methyl orethyl are preferred;

The mononuclear aryl radicals include unsubstituted phenylene radicalsand phenylene radicals containing one or more inert substituents such asalkyl, alkoxy, halogen or acylamino substituents; for example, tolylene,

chlorophenylene, bromophenylene, Compounds in which they are.mononuclear aryl. hydrocarbon radicals, and especially phenylene, arepre-Y methoxyphenylene, etc.

ferred.

The sulfonarnide radicals of the compounds. of present invention includevarious types of such radicals. f, Thus they include sulfonamideradicals in which the radi cal attached to the sulfon group is an alkyl,cycloalkyl, a sultani aralkyl, aryl,.or heterocyclic radical, or part of(in which the group is linked to diiferentjcarbon atoms of thesame'radical), a number of which are illustrated below.

Patented Aug. '9, 1960 They also include radicals in which the hydrogenatom of the group is substituted by an alkyl, cycloalkyl, aralkyl, arylor heterocyclic radical. Preferably they are free from chromophoricgroups and from acidic groups containing a hydrogen cation, which wouldinterfere with their use as leuco electron-donor color reactants. Theymay, however, contain such substituents as alkyl, alkoxy, halogen,dialkylamino, acylamino and sulfonamido groups.

The N-bis (p-dialkylaminoaryl)methyl sulfonamides of the presentinvention have the formula wherein:

R R R and R are each an alkyl radical having 1 to 5 carbon atoms (suchas, methyl, ethyl, propyl, butyl or amyl),

R is selected from the group consisting of alkyl (such as, methyl,ethyl, propyl, butyl, amyl, hexyl, octyl, dodecyl, hexadecyl, octadecylor octadecenyl), cycloalkyl (such as, cyclopentyl, cyclohexyl or methylcyclohexyl), aralkyl (such as, benzyl or phenylethyl), aryl (such as,phenyl, tolyl, xylyl, naphthyl, biphenyl or indene) and heterocyclic(such as, pyridyl, quinolyl, benzothiazyl, benzofuryl or pheuothiazyl)radicals, including substituted derivatives of such radicals andpreferably those free from chromophoric groups and from acidic groupscontaining a hydrogen cation (such as the alkyl, alkoxy, fluorine,chlorine, bromine, dialkylamino, acylamino or sulfamido derivatives ofthe radicals referred to above), and sultam radicals which are part ofthe same radicals jointly with R (such as, naphthsultam) R is selectedfrom the group consisting of hydrogen and the radicals represented by Rand are selected from the group consisting of the phenylene radical andsubstituted derivatives thereof, preferably those free from chromophoricgroups and from acidic groups containing a hydrogen cation (such as theallryl, alkoxy, fluorine, chlorine, bromine, dialkylamino, acylamino orsulfamido derivatives thereof).

Those compounds are of particular value in which R R, R and R are methylor ethyl, the phenylene radicalls are mononuclear aryl hydrocarbonradicals, R is hydrogen or methyl, and R is phenyl, tolyl,methoxyphenyl, or dimethylaminophenyl.

The compounds of the present invention are soluble in a wide variety ofnon-polar organic solvents, such as benzene, toluene, kerosene, mineraloil, dioctylphthalate, chlorinated biphenyls, etc. When applied as asolution in such solvents to a paper or other material coated with anacidic material, such as bentonite, kaolin, felspar, monoor dibasicbarium or calcium phosphates, they produce generally greenish blue toviolet colorations. In addition, by virtue of the sulfonamido radical,they possess relatively low volatility and high stability to air andlight. These advantageous properties render the lightly colored tocolorless sulfonamides of the present invention outstanding for use insystems of the above type.

Thus, the compounds of the present invention are useful in the formationof colored compounds or difierently colored compounds by contact withelectron acceptor or acidic materials which cause a rearrangement of thechemical molecule with intensification of the color thereof, such asthose enumerated above.

Lightly colored, and especially colorless or substantially colorless,compounds of this invention are particularly useful in so-calledcolorless carbon papers and duplicating manifold record systems of thetype referred to above, because of their superior stability both in theleuco form and in the colored form obtained by contact with an acidicelectron acceptor. Thus, in the leuco form they are stable to storage incontainers open to the atmosphere, as well as when incorporated intorecord sheets of the type disclosed in US. Patents 2,548,366 and2,712,507 and exposed to the atmosphere and to light. In the form ofcolored compounds formed by contact with acidic electron acceptors ofthe type referred to above, they are stable to light and to theatmosphere, even when embodied as record sheet material exposed tosunlight. This is in contrast to N-phenyl leucoaurarnine and relatedcompounds, which when incorporated into record sheet material of thetype disclosed, for example, in U.S. Patents 2,548,366 and 2,712,507,are unstable and/or volatilize or rapidly become ineffective; and incontrast to the rapid fading of the color produced by contact of acidicclays with crystal violet lactone heretofore employed commercially.Further, they do not stain the skin when the record sheets are handled.

For example, when the compound of Example 1 of the present applicationis substituted for the mixture of crystal violet lactone and methylenebase employed in Example 1 of U.S.P. 2,548,366, the resulting sheets arestable during storage for long periods of time and when placed one abovethe other, with the claycoated surfaces upward, and marked with astylus, a blue marking is de veloped on the clay-coated surface of thelower sheet where pressure was applied, which marking does not fade.

The sulfonamidcs of the present invention can be prepared in variousways. The simplest method from the standpoint of availability ofstarting materials and apparatus required involves the condensation of abis(p-dialkylaminoaryl)methyl hydrol having the formula R H Ra Rf AB Rwith a sulfonamide having the formula RHSOQNH wherein R R R R R R havethe meaning given above, preferably in substantially equimolar amounts.The condensation is preferably carried out by heating in a solvent at atemperature between and C. (All ranges given herein, including theclaims, are inclusive of the limits.)

The general method of preparation preferably Consists in refluxingsubstantially equimolecular proportions of the benzhydrol and of thesulfonamide in a suitable solvent having a boiling point between 80 and150 C., at least a fraction of each of the two reactants being solublein the solvent. Suitable solvenm are for example, hydrocarbon solvents,such as petroleum hydrocarbons (such as 2,2,4-trimethylpentane and lowboiling kerosene frac tions), aromatic hydrocarbons (such as benzene,toluene or xylene), and mixtures preferably having a boiling rangebetween 80 and 150 C., and alcohols, such as ethyl, propyl or butylalcohols or mixtures thereof. When effected in a hydrocarbon solvent,water formed in the reaction is preferably removed. Thebis(p-dialkylaminoaryl)methyl sulfonamides thus obtained may be purifiedby recrystallization from a suitable solvent.

. The following are illustrative of hydrols which are suitable for usein the process: I Michlers hydrol: 4,4-bis(dimethylamino)benzhydrol4,4'-bis(diethylamino) benzhydrol 4,4'-bis(dipropylamino)benzhydrol4,4-bis(dibutylamino) benzhydrol 4,4'-bis( dimethylamino)-2,2'-dichloro-benzhydrol 4,4-bis( dimethylamino)3,3-dimethyl-benzhydrol 4,4'-bis(diethylamino) -2,2'-dibromo-benzhydrolThe following are illustrative of sulfonarnides which are suitable foruse in the process, alone or in the formof mixtures of two or more ofthem Methane sulfonamide Ethane sulfonamide Propane sulfonamides Butanesulfonamides Pentane sulfonamides Hexane sulfonamides Octanesulfonamides Decane sulfonamides Dodecane sulfonamides, especially thenormal primary Hexadecane sulfonamides, especially the normal primaryOctadecane sulfonamides, especially the normal primary Octadecenesulfonamide (oleyl sulfonamide) Mixtures of sulfonamides derived fromsulfuryl chloride reaction products of hydrocarbon mixtures Cyclopentanesulfonamide Cyclohexane sulfonamide Methyl-cyclohexane sulfonamideN-methyl-cyclohexane sulfonarnide Phenylmethane sulfonamide (benzylsulfonamide) Phenylethane sulfonamide Benzene sulfonamide 4-toluenesulfonamide 4-chlorobenzene sulfonamide 4-methoxybenzene sulfonarnide4-dimethylaminobenzene sulfonamide 4-diethylaminobenzene sulfonamide4-di-n-butylaminobenzene sulfonamide N-methyl-benzene sulfonanu'de1.3-benzene disulfonamide l-naphthalene sulfonarnide Z-naphthalenesulfonamide 4-diphenyl sulfonarnide 4-indene sulfonamide 3-py'ridinesulfonamide 6-quinoline sulfonamide Z-benzothiazole sulfonamidefi-benzothiazole sulfonamide S-benzofurane sulfonamide 3-phenothiazinesulfonamide Naphthosultam The invention will be illustrated by thefollowing specific examples, but it is to be understood that it is notlimited to the details thereof and that changes may be made withoutdeparting from the scope of the invention. The temperatures are indegrees centigrade and the parts and percentages are by weight, tmlessdesignated as parts by volume. Where parts are by volume, the amountsignifies the volume occupied by the same number of parts by weight ofwater at 4 C.

Example 1 water separator of the conventional type whichcontinutagitator, and a reflux condenser connected to a ously collectsthe reflux condensate of water, benzene and toluene, separates the waterfrom the hydrocarbons, and

returns the latter to the reaction. The charge was heated to boiling andrefluxed (at about 100) for 40 hours,

while removing the water generated by the condensation reaction. Thereaction mix 'ture was then cooled to room temperature, and theresulting needle-like crystals were separated by filtration.

The crude product thus obtained was recrystallized first from benzene(about 400 parts by volume) and then from toluene (about 500 parts byvolume), and dried in a vacuum drier. In carrying out theserecrystallizations, the crude crystals were dissolved in the hot solventand adecolorizing carbon (Nuchar) was added in an amount about 1 to 5%of the weight of the crystals, after which the hot mixture was sludgefiltered and the filtrate was allowed to cool, to crystallize thepurified product.

The product thus obtained as white crystals having a melting point of174-176, uncorrected, wasphenylsulsulfonamidobis(pdimethylaminophenyl)methane of the formulaExample 2 A mixture of 60 parts of Michlers hydrol, technical grade(equivalent to 0.2 mol of 100%), 34 parts of ptoluenesulfonamide(equivalent to 0.2 mol), 4 parts by volume of 25% aqueous sodiumhydroxide and 350 parts by volume of toluene was refluxed for 32 hoursas in Example 1, to complete the condensation reaction. The

mixture was then cooled and filtered. The crude prodnot thus obtainedwas recrystallized from 300 parts by volume of toluene in the presenceof a small amount of a decolon'zing carbon (Nuchar).

The purified product thus obtained as white crystals melting at 180181,uncorrected, was p-tolysulfonamido bis(p dimethylaminophenyhmethane.When a toluene solution thereof was contacted with bentonite a bluecoloration was produced.

Example 3 The procedure of Example 2 was repeated using 37.4 parts otp-methoxybenzenesulfonamide (0.2 mol) in place of thep-toluenesultonamide, and 500 parts by volume rather than 350 parts byvolume of toluene.

The purified product thus obtained as white crystals melting at -177,uncorrected, was p-methoxyphenylsulfonamido bis(pdimethylaminophenyl)methane. A solution thereof in toluene when spottedon bentonite.

Example 4 The procedure of Example 3 was repeated using methane. Asolution thereof in toluene gave a [blue color, when spotted onbentonite. i

gave a blue color bite crystals? uncorrected, was pdimethyl eaminophenylsulfonamido bis(p-dimethylaminophenyl) Example A mixture of51.8 parts of Michlers hydrol, technical grade (equivalent to 0.175 molof 100%), 42.6 parts of p-diethylaminobenzenesulfonamide, 4 parts byvolume of 25% aqueous sodium hydroxide, and 250 parts by volume oftoluene was. boiled and refluxed for 12 hours, while continuouslyremoving water as in Example 1. The hot reaction mixture, after dilutionwith 25 0 parts by volume of toluene and reheating to produce a clearsolution, was sludge filtered hot and the filtrate was allowed to coolto room temperature. The crystals thus obtained were separated =byfiltration and dried in a vacuum drier at about 40. The crude crystalswere recrystallized from toluene (500 parts by volume) in the presenceof a small amount of decolorizing charcoal (Nuchar) and dried as inExample 1.

The product thus obtained as white crystals melting at 145 -150,uncorrected, was p-diethylaminophenylsulfonamido bis(pdimethylaminophenyl)methane. A solution thereof in toluene produced agreenish blue color when spotted on bentonite.

Example 6 A mixture of 30 parts of Michlers hydrol (90% strength,equivalent to 0.1 mol), 28.4 parts (0.1 mol) ofp-di-n-butylaminobenzenesulfonamide (having a melting point 132-l34 and250 parts by volume of toluene was heated to boiling and refluxed (112)for 48 hours to complete the condensation reaction. The mixture was thencooled to room temperature and filtered. The crystals were washed with25 parts by volume of toluene and dried in a vacuum drier at 3035.

The crystalline product thus obtained,p-di-n-butylaminophenylsulfonamido bis(p dimethylaminophenyl) methane,was essentially colorless and had a melting point of 171-173. A toluenesolution thereof spotted on paper coated with bentonite produced a bluecoloration.

Example 7 The procedure of Example 3 was repeated using 66.6 parts (0.2mol) of octadecanesulfonamide in place of thep-methoxybenzenesulfonamide.

The product thus obtained as essentially colorless crystals wasoctadecylsulfonamido-bis(p-dimethylaminophenyl)methane having theformula:

Us: {I /CHs CH: IYTH CH:

CxsHavSOz When a solution thereof in toluene was spotted on bentonite, ablue coloration was obtained.

Example 8 The procedure of Example 3 was repeated using 41.4 parts ofl-naphthalenesulfonamide (0.2 mol) in place of thep-methoxybenzenesulfonamide.

The product thus obtained as colorless crystals was 1-naphthylsulfonamido bis(p dimethylaminophenyl)- methane. When dissolvedin toluene and spotted on bentonite, a blue coloration was produced.

Example 9 A mixture of 30 parts of Michlers hydrol (0.1 mol of 100%),20.5 parts of naphthosultam (0.1 mol of 100%), and 175 parts by volumeof ethyl alcohol (213 denatured) was heated to boiling and refluxed(7880) for 50 hours. The mixture was then cooled to room temperature andfiltered.

The crystals were dissolved in 500 parts by volume of a mixture of equalvolumes of toluene and isopropyl alcohol, at the boil. The solution wascharged with 2 parts of decolorizing carbon (Nuchar) and sludgefiltered. The filtrate was cooled to room temperature and filtered.

8 The nearly white crystalline product thus obtained was naphthosultamylbis(p dimethylaminophenyl)methane having the formula Cg: 1?: CH3

) O CH; I OH:

It decomposed at 223 when heated. When a solution thereof in toluene waspoured onto paper coated with hentonite clay, a blue coloration wasobtained.

Example 10 The procedure of Example 3 was repeated using 31.6 parts (0.2mol) of 3-pynidinesulfonamide in place of thep-methoxyphenylsulfonamide.

The purified product thus obtained was 3-pyn'dylsulfonamido-bis(p-dimethylaminophenyl)methane having the formula CE: /CH3 CH3 l C Ha NN -H It was essentially colorless, and when dissolved in toluene andspotted on bentonite, gave a blue color.

Example 11 A mixture of 32.6 parts of 4,4-bis(diethylamino)benz hydrol(0.1 mol of 100%, 15.7 parts of benzenesulfonamide (0.1 mol of 100%),and 200 parts by volume of ethyl alcohol (2B denatured) was heated torefluxing for 50 hours. The reaction mixture was sludge filtered hot,and the filtrate was cooled to 0 for 3 days. The tacky crystals thusobtained were filtered oil and dried in vacuo at 30-35 The product wasrecrystallized from ethyl ether, yieldingphenylsulfonamido-bis(p-diethylaminophenyl)methane, i.e.,N-bis(p-diethylaminophenyl)methyl benzenesulfonamide, in the form ofgray crystals melting at 155 uncorrected. When dissolved in toluene andpoured onto paper coated with bentonite, a greenish blue color wasslowly produced, which overnight became deep reddish blue.

Example 12 A mixture of 27 parts of Michlers hydrol (0.1 mol of 20.7parts of Z-naphthalenesulfonamide (0.1 mol) and 200 parts by volume oftoluene was refluxed at 112 for 40 hours, while removing water as inExample 1, until the condensation was complete. The reaction mixture wassludge filtered at room temperature. The filtrate was refrigerated to-10", and the crystals obtained were filtered off and dried.

The crude crystals thus obtained were recrystallized from toluene. Thepurified product thus obtained as tan crystals having a melting point of164, uncorrected, was2-naphthylsulfonamido-bis(p-dimethylaminophenyDmethane. A solutionthereof in toluene when spotted on paper coated with bentonite graduallygave a greenish blue color, which overnight became deep reddish blue.

Example 13 32.6 parts of 4,4'-bis(diethylamino)benzhydrol (0.1 mol of100%), 17.1 parts of p-toluenesulfonamide (0.1 mol), and 250 parts byvolume of toluene was refluxed at 113 for 32 hours, while separatingwater as in Example 1. The reaction mixture was sludge filtered hot,

the filtrate was cooled to and the resulting crystals were filtered ofrand dried in vacuo at 3035.

The product thus obtained as cream colored crystals melting at 142,uncorrected, was p-tolylsulfonamido-bis- (p-diethylaminophenyl) methane.When a solution thereof in toluene was spotted on bentonite, a greenishblue color formed gradually and became deep reddish blue overnight.

It will be evident to those skilled in the art that the invention notlimited to the details of the foregoing illustrative examples and thatchanges can be made without departing from the scope of the invention.

Thus, instead of the hydrols and sulfonamides employed in the examples,others of those specified above may be substituted in equivalentamounts. Further instead of the hydrol, the corresponding bis(p-dialkylaminoaryDmethyl chloride or bromide may be used.

The Michlers hydrol employed in certain of the examples was a technicalproduct containing mineral acid impurities. Accordingly such examplesinclude the addition of a small amount of sodium hydroxide to neutralizesaid impurities. Other neutralizing agents can be used similarly, suchas sodium carbonate.

I claim:

1. N-bis(p-dialkylaminoaryl)methyl sulfonamides in which the alkylgroups of the dialkylamino radicals each have 1 to carbon atoms; thearyl radicals are each selected from the group consisting of phenyleneand phenylene monosubstituted by a member of the group consisting oflower alkyl, lower alkoxy, fluorine, chlorine, bromine, di-loweralkylamino, lower alkanoylamino, and 'SO NH and the sulfonamide radicalshave the formula:

wherein:

R represents a radical selected from the group consisting of (A) alkylup to 18 carbon atoms; octadecenyl; cycloalkyl in which the ringcontains 5 to 6 carbon atoms; phenyl-lower alkyl; (B) phenyl, tolyl,xylyl, naphthyl, biphenyl, indenyl, pyridyl, quinolyl, benzothiazyl,benzofuryl and phenothiazyl, and the radicals of (B) monosubstituted bya member of the group consisting of lower alkyl, lower alkaxy, fluorine,

chlorine, bromine, di-lower alkylamino, lower alkanoylamino and -SO NHand the naphthosultam radical which is part of the same radical jointlywith R and R represents a radical selected from the group consisting ofhydrogen and the radicals represented by R 2.N-bis(p-dialkylaminoaryl)methyl alkyl sulfonamides having 1 to 18 carbonatoms in the alkyl group in which the alkyl groups of the dialkylaminoradicals each have 1 to 2 carbon atoms, and the aryl radicals aremononuclear aryl hydrocarbon radicals.

3. N-bis(p-dialkylaminoaryl)methyl aryl sulfonamides in which the alkylgroups of the dialkylarnino radicals each have 1 to 2 carbon atoms, andthe aryl radicals are mononuclear aryl hydrocarbon radicals.

4. N-bis(p-dialkylaminophenyl)methyl alkyl sulfonamides having 1 to 18carbon atoms in the alkyl group the alkyl groups of the dialkylaminoradicals each hav ing 1 to 2 carbon atoms.

5. N-bis(p-dialkylaminophenyl)methyl aryl sulfonamides the alkyl groupsof the dialkylamino radicals each having 1 to 2 carbon atoms and thearyl radical is a mononuclear aryl hydrocarbon radical.

6. N-bis(p-dimethylaminophenyl)methyl alkyl sulfonamides having 1 to 18carbon atoms in the alkyl group.

7. N-bis(p-dimethylaminophenyl)methyl cycloalkyl sulfonamides in whichthe cycloalkyl ring contains 5 to 6 carbon atoms.

8. N-bis(p-dimethylarninophenyl)methyl phenyl-lower alkyl sulfonamides.

9. N-bis (p-dimethylaminophenyl)methyl aryl sulfonamides in which thearyl radical is a mononuclear aryl hydrocarbon radical.

10. N-bis(p dimethylaminophenyl)methyl phenylsulfonarnide.

l1. N-bis(p-dimethylaminophenyl)methyl naphthylsulfonarnide.

12. N-bis(p dimethylaminophenyl)methyl p-tolylsulfonarnide.

l3. N-bis(p-dimethylaminophenyl)methyl p-methoxyphenylsulfonamide.

14. N-bis(p-dimethylaminophenyl)methyl p-dimethylaminophenylsulfonamide.

References Cited in the file of this patent Bogert et al.: I. Am. Chem.Soc., vol. 44, pp. 2612-21 (1922).

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No, 2 948753 August 9, 1960 Frederick H. Kranz It is hereby certified that errorappears in the printed specification of the above numbered patentrequiring correction and that the said Letters Patent should read ascorrected below.

line 43 for "crystalline" read crystal for "'4-diphenyl sulfonamide"read column 6 line 2O for line 51 Example 2, for ulfon-a- -gcolumn 8,line 3'7, 100%) column 9, line ll Column 1,

column 5, line 46 4-biphenyl sulfonamide "phenylsul read phenyl"ptolysulfon-" read p-t0lyls Example 11, for "100% read for "alkaxy"read alkoxy Signed and sealed this 4th day of April 1961.

(SEAL) Att ERNEST W. SWIDER XXXXXXEEW ARTHUR w. CROCKER AttestingOfiicer Acting Commissioner of Patents

1. N-BIS(P-DIALKYLAMINOARYL)METHYL SULFONAMIDES IN WHICH THE ALKYLGROUPS OF THE DIALKYLAMINO RADICALS EACH HAVE 1 TO 5 CARBON ATOMS, THEARYL RADICALS ARE EACH SELECTED FROM THE GROUP CONSISTING OF PHENYLENEAND PHENYLENE MONOSUBSTITURED BY A MEMBER OF THE GROUP CONSISTING OFLOWER ALKYL, LOWER ALKYL, FLUORINE CHLORIEN, BROMINE, DI-LOWERALKYLAMINO, LOWER ALKANOYLAMINO, AND -SO2NH2, AND THE SULFONAMIDERADICALS HAVE THE FORMULA: